Optical jog wheel with spiral coding element

ABSTRACT

A user navigational apparatus. The user navigational apparatus includes a dial, a coding element, and an encoder. The coding element is coupled to a dial. The coding element includes a track of alternating reflective and non-reflective sections, each having a substantially oblique leading edge relative to a direction of movement of the coding element. The encoder includes an emitter and a detector. The emitter generates a light signal incident on the track of the coding element. The detector detects a reflected light signal which corresponds to a portion of the incident light signal that is reflected off of the reflective sections of the track. The detector also generates a channel signal corresponding to the reflected light signal.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation-in-part of patent application Ser. No.11/591,799, filed Nov. 1, 2006, which is incorporated by referenceherein.

BACKGROUND OF THE INVENTION

A jog wheel is a type of device to allow a user to navigate throughaudio or video content. As the jog wheel is turned, the media typicallyshifts in a direction (e.g., fast-forward, reverse, left, and right)according to which way the wheel is turned. For example, if the userturns the jog wheel clockwise, then the media typically advances. Incontrast, if the user turns the jog wheel counter-clockwise, then themedia typically reverses. Jog wheels also have been implemented asscroll wheels on computer mice. More recently, jog wheels also have beenimplemented as menu selection interfaces on devices such as personaldigital assistants and music players. For example, jog wheels may beused to scroll through menu entries and to make menu selections.

The speed at which the media advances or reverses (or the menuselections scroll) typically depends on how the jog wheel is turned. Howthe user turns, or simulates turning, the jog wheel is a function of thetype of jog wheel that is implemented. For multi-spin jog wheels, thejog wheel may be rotated endlessly, so that the speed at which the mediaadvances or reverses usually corresponds to how fast the user rotatesthe jog wheel. For single-turn jog wheels, the rotational movement ofthe jog wheel is limited (e.g., typically limited to less than one fullrotation) by fixed stops, and the speed at which the media advances orreverses usually corresponds to how far toward one side the user rotatesthe jog wheel.

A jog wheel also may be referred to as a jog dial, a shuttle dial, or ashuttle wheel. In some instances, the term “jog” is used to refer toslow navigational speeds, while the term “shuttle” is used to refer tofast navigational speeds. However, no distinction between “jog” and“shuttle” is made in the present description.

Conventionally, two technologies have been used to implement jog wheels.Specifically, conventional jog wheels are typically implemented usingeither capacitive sensing or magnetic sensing. In one conventionalimplementation of capacitive sensing, the jog wheel has a capacitivecircuit such as one or more layers of conductive traces built into it todetect a change in capacitance due to the movement of a nearbyconductive object such as a user's finger. In some instances, thecapacitive jog wheel does not actually rotate, but the capacitivecircuitry senses the simulated rotation by a finger, stylus, or otherconductive object.

In magnetic sensing implementations, the jog wheel may be implementedwith a hall effect sensor. A hall effect sensor is a transducer thatgenerates a voltage in response to a change in the magnetic fielddensity. Typically, the hall-effect sensor detects a magnetic field froma passing current-carrying conductor (or, alternatively, detects achanging current in a fixed conductor). By arranging thecurrent-carrying conductor and the sensor in relative positions on andoff the jog wheel, the hall effect sensor can detect the rotation of thejog wheel. If multiple hall effect sensors are used, the circuitry maybe able to indicate partial rotation of the jog wheel and the rotationaldirection of the jog wheel.

The use of these conventional technologies may result in relativelythick jog wheels. In other words, the size of the jog wheel may berelatively big. Having a jog wheel that is large in size limits thepotential use of jog wheels in some applications, especially in smallhandheld computer devices or other small devices. Also, the resolutionof conventional jog wheels may be limited to the resolution of thecapacitive traces or the number of hall effect sensors implemented inthe jog wheel. In the case of capacitive jog wheels, the resolution istypically limited by the size of the conductive object, e.g., fingertip,used as the input device. In the case of hall effect jog wheels,increasing resolution by implementing several hall effect sensors isgenerally cost-prohibitive.

In view of this, what is needed is a jog wheel to overcome the physicalsize and resolution limitations of conventional jog wheels.

SUMMARY OF THE INVENTION

Embodiments of a user navigational apparatus are described. The usernavigational apparatus includes a dial, a coding element, and anencoder. The coding element is coupled to a dial. The coding elementincludes a track of alternating reflective and non-reflective sections,each having a substantially oblique leading edge relative to a directionof movement of the coding element. The encoder includes an emitter and adetector. The emitter generates a light signal incident on the track ofthe coding element. The detector detects a reflected light signal whichcorresponds to a portion of the incident light signal that is reflectedoff of the reflective sections of the track. The detector also generatesa channel signal corresponding to the reflected light signal.

In some embodiments, the user navigational apparatus also includes adecoder and a microprocessor. The decoder generates a count signalcorresponding to the channel signal. The microprocessor implements auser navigational operation on a controlled device in response to amovement of the dial by a user. The user navigational apparatus also mayinclude an independent button, an illumination ring, a back plate, acircuit substrate, and a mounting bracket. Other embodiments of the usernavigational apparatus are also described.

Embodiments of a method for making a user navigational apparatus arealso described. In one embodiment, the method includes coupling a spiralcode wheel to a rotary dial, mounting an emitter on a circuit substraterelative to the spiral code wheel, and mounting a detector on thecircuit substrate relative to the spiral code wheel. Other embodimentsof the method for making a user navigational apparatus are alsodescribed.

Other aspects and advantages of embodiments of the present inventionwill become apparent from the following detailed description, taken inconjunction with the accompanying drawings, illustrated by way ofexample of the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a schematic circuit diagram of one embodiment of anoptical reflective jog wheel.

FIG. 2 depicts a partial schematic diagram of one embodiment of a codewheel.

FIG. 3 depicts a perspective view of one embodiment of an optical jogwheel.

FIG. 4 depicts a side view of the optical jog wheel of FIG. 3.

FIG. 5 depicts an exploded perspective view of the optical jog wheel ofFIG. 3.

FIG. 6 depicts one embodiment of a layout of an encoder on a circuitsubstrate.

FIG. 7 depicts a side view of one embodiment of a layout of an encoderwith an air gap between the encoder and the code wheel.

FIG. 8 depicts a side view of one embodiment of a layout of an encoderwith a fully encapsulated encoder.

FIG. 9 depicts a side view of one embodiment of a layout of an encoderwith an individually encapsulated emitter and detector.

FIG. 10 depicts a side view of one embodiment of a layout of an encoderwith an individually encapsulated emitter and a partially encapsulateddetector.

FIG. 11 depicts one embodiment of a method of making an optical jogwheel.

FIG. 12 depicts one embodiment of a method of using an optical jogwheel.

FIG. 13 depicts a perspective view of another embodiment of an opticaljog wheel.

FIG. 14 depicts a side view of the optical jog wheel of FIG. 13.

FIG. 15 depicts an exploded perspective view of the optical jog wheel ofFIG. 13.

FIG. 16 depicts a partial schematic diagram of another embodiment of acode wheel with spiral track sections.

FIG. 17 depicts a layout of one embodiment of a photodetector arrayrelative to spiral track sections of the code wheel of FIG. 16.

FIG. 18 depicts a schematic diagram of one embodiment of a code stripwith diagonal track elements.

FIG. 19 depicts one embodiment of a method of making an optical jogwheel with the spiral code wheel of FIG. 16.

Throughout the description, similar reference numbers may be used toidentify similar elements.

DETAILED DESCRIPTION

FIG. 1 depicts a schematic circuit diagram of one embodiment of anoptical jog wheel 100. The illustrated optical jog wheel 100 includes arotary dial 102, a code wheel 104, an encoder 106, a decoder 108, and amicroprocessor 110. In one embodiment, the rotary dial 102 is physicallycoupled to the code wheel 104 and provides a tactile interface for auser to manually turn the code wheel 104. In some embodiments, therotary dial 102 is a multiple-turn dial that may be turned endlessly.Alternatively, the rotary dial 102 may be a single-turn dial with arange of motion that is limited to approximately one revolution (i.e.,360 degrees) or less. The type of code wheel 104implemented—multiple-turn or single-turn—corresponds to the type ofrotary dial 102 that is used.

Although a more detailed illustration of the code wheel 104 is providedin FIG. 2, a brief explanation is provided here as context for theoperation of the optical jog wheel 100 shown in FIG. 1. In general, thecode wheel 104 includes a track 140 of non-reflective sections 142 andreflective sections 144. An emitter 120 in the encoder 106 produceslight that is incident on the code wheel track 140. As the rotary dial102 is rotated, the incident light is reflected by the reflectivesections 144 of the track 140, but is not reflected by thenon-reflective sections 142 of the track 140. Thus, the light isreflected by the track 140 in a modulated pattern (i.e., on-off-on-off .. . ). A detector 130 in the encoder 106 detects the modulated,reflected light signal and, in response, generates one or more channelsignals (e.g., CH_(A) and CH_(B)). In one embodiment, these channelsignals are then transmitted to the decoder 108, which generates a countsignal and transmits the count signal to the microprocessor 110. Themicroprocessor 110 uses the count signal to implement a usernavigational operation such as scrolling or menu selection correspondingto the movement of the rotary dial 102.

In one embodiment, the encoder 106 includes the emitter 120 and thedetector 130. The emitter 120 includes a light source 122 such as alight-emitting diode (LED). For convenience, the light source 122 isdescribed herein as an LED, although other light sources, or multiplelight sources, may be implemented. In one embodiment, the LED 122 isdriven by a driver signal, V_(LED), through a current-limiting resistor,R_(L). The details of such driver circuits are well-known. Someembodiments of the emitter 120 also may include a lens 124 aligned withthe LED 122 to direct the projected light in a particular path orpattern. For example, the lens 124 may focus the light onto the codewheel track 140.

In one embodiment, the detector 130 includes one or more photodetectors132 such as photodiodes. The photodetectors may be implemented, forexample, in an integrated circuit (IC). For convenience, thephotodetectors 132 are described herein as photodiodes, although othertypes of photodetectors may be implemented. In one embodiment, thephotodiodes 132 are uniquely configured to detect a specific pattern orwavelength of reflected light. In some embodiments, several photodiodes132 may be used to detect modulated, reflected light signals frommultiple tracks 140, including positional tracks and index tracks. Also,the photodiodes 132 may be arranged in a pattern that corresponds to theradius and design of the code wheel 104.

The signals produced by the photodiodes 132 are processed by signalprocessing circuitry 134 which generates the channel signals, CH_(A) andCH_(B). In one embodiment, the detector 130 also includes one or morecomparators (not shown) to facilitate generation of the channel signals.For example, analog signals (and their complements) from the photodiodes132 may be converted by the comparators to transistor-transistor logic(TTL) compatible, digital output signals. In one embodiment, theseoutput channel signals may indicate count and direction information forthe modulated, reflected light signal. Additionally, the detector 130may include a lens 136 to direct the reflected light signal toward thephotodiodes 132.

Additional details of emitters, detectors, and optical encoders,generally, may be referenced in U.S. Pat. Nos. 4,451,731, 4,691,101,5,017,776, and 5,241,172, which are incorporated by reference herein.

FIG. 2 depicts a partial schematic diagram of one embodiment of a codewheel 104. In particular, FIG. 2 illustrates a portion of a circularcode wheel 104 in the shape of a disc. In some embodiments, the codewheel 104 may be in the shape of a ring, rather than a disc. Theillustrated code wheel 104 includes a track 140, which may be a circulartrack that is concentric with the code wheel 104. In one embodiment, thetrack 140 includes a continuous repeating pattern that goes all the wayaround the code wheel 104. The depicted pattern includes alternatingnon-reflective sections 142 and reflective sections 144, although otherpatterns may be implemented. In one embodiment, the non-reflectivesections 142 are transparent sections of the code wheel 104 or,alternatively, are voids (e.g., holes) in the code wheel 104. Thereflective sections 144 are, for example, opaque sections in the codewheel 104. In one embodiment, the surface areas corresponding to thereflective sections 144 are coated with a reflective material.

Also, it should be noted that, in some embodiments, the circular codewheel 104 could be replaced with a coding element that is not circular.For example, a linear coding element such as a code strip may be used,in which case a linear slider (not shown) may be implemented instead ofthe rotary dial 102. In another embodiment, a circular coding elementmay be implemented with a spiral bar pattern, as described in U.S. Pat.No. 5,017,776, as shown in FIG. 16 and described in more detail below.Furthermore, a linear coding element such as a code strip may beimplemented with a spiral, or diagonal, bar pattern, as shown in FIG. 17and described in more detail below. Alternatively, other lightmodulation patterns may be implemented on various shapes of codingelements.

As described above, rotation of the code wheel 104 and, hence, the track140 results in modulation of the reflected light signal at the detector130 to measure positional changes of the code wheel 104 and the dial102. Other embodiments of the code wheel 104 may include other trackssuch as additional positional tracks or an index track, as are known inthe art.

In the depicted embodiment, the track sections 142 and 144 have the samecircumferential dimensions (also referred to as the width dimension).The resolution of the code wheel 104 is a function of the widthdimensions (as indicated by the span “x”) of the track sections 140 and142. The radial, or height, dimensions (as indicated by the span “y”) ofthe track sections 140 and 142 are a function of the amount of arearequired to generate a sufficient amount of photocurrent (e.g., the morephotocurrent that is required, the larger the area required and hencethe larger “y” needs to be since area equals “x” times “y”).Additionally, the radial dimensions of the track sections 140 and 142may be a function of the amount of area required to produce a detectablegap between consecutive, reflected light pulses.

In another embodiment, the code wheel 104 may be at least partiallyintegrated with the dial 102, rather than being a separate componentcoupled to the dial 102. For example, the underside of the dial 102 maybe coated with reflective material such as bright nickel (Ni) or chrome,and a non-reflective track pattern can be applied to the reflectivematerial. The non-reflective pattern may be silk-screened, stamped, inkjet printed, or otherwise applied directly onto the reflective surfaceon the dial 102. Alternatively, the non-reflective pattern may be formedas a separate part such as by injection molding, die-cutting, punching(e.g., film), or otherwise forming a non-reflective component which hasopaque spokes on it. Whether the non-reflective material is applieddirectly to the reflective material or formed as a separate component,the combined reflective and non-reflective materials function similar tothe code wheel 104 described above, having alternative reflective andnon-reflective sections 142 and 144. In another embodiment, thereflective and non-reflective materials may be reversed so that theunderside of the dial 102 is used for the non-reflective material and aseparate reflective material is applied to or formed separately from thenon-reflective material.

FIG. 3 depicts a perspective view of one embodiment of an optical jogwheel 150. The illustrated optical jog wheel 150 includes a rotary dial102, a code wheel 104 (not shown in FIG. 3), a circuit substrate 152,and a back plate 154. FIG. 4 depicts a side view of the optical jogwheel 150 of FIG. 3.

In one embodiment, the rotary dial 102 includes a tactile surface tofacilitate rotation of the rotary dial 102 by a user. For example, therotary dial 102 may include raised or dimpled portions, a rough surface,a tacky surface, or another tactile surface to make it relatively easyfor a user's finger to engage the surface of the rotary dial 102. Asdescribed above, the code wheel 104 is coupled to the rotary dial 102 sothat the rotation of the rotary dial 102 results in a correspondingrotation of the code wheel 104.

In one embodiment, the circuit substrate 152 is used to mount theencoder 106, including the emitter 120 and the detector 130. Someexemplary types of circuit substrates 152 include, but are not limitedto, printed circuit board (PCB), flexible circuit, leadframe, insertmolded leadframe, glass substrate, ceramic substrate, moldedinterconnect device (MID), and so forth. Alternatively, other types ofcircuit substrates 152 may be implemented. In some embodiments, othercircuitry also may be mounted on the circuit substrate 152. However, insome embodiments, the amount of circuitry mounted to the circuitsubstrate 152 under the rotary dial 102 may be limited to keep thethickness of the optical jog wheel 150 small. The circuit substrate 152is mounted to the back plate 154. Alternatively, the circuit substrate152 also may be used as the back plate, in some embodiments, so that aseparate back plate 154 may be omitted.

The illustrated optical jog wheel 150 also includes an independentbutton 154 and an illumination ring 156, although some embodiments mayomit the independent button 156, or the illumination ring 158, or both.The independent button 156 may be implemented with a dome switch (notshown) or another well-known type of actuator. Alternatively, theindependent button 156 may be implemented using an optical sensor whichgenerates a button click signal in response to depression of theindependent button. In a similar manner, some embodiments implement theencoder 106 to detect one or more button click operations correspondingto a depression of at least a portion of the rotary dial 102. In anembodiment, depression of the independent button or the rotary dialcorresponds to a directional selection or to an item selection.

In one embodiment, the illumination ring 158 illuminates upon userinteraction with the optical jog wheel 150, including rotation of therotary dial 102, depression of the rotary dial 102, or depression of theindependent button 156. The illumination ring 158 also may be used toengage with the back plate 154 to secure the other components of theoptical jog wheel 150 such as the code wheel 104, rotary dial 102, andindependent button 156 to the back plate 154. In some embodiments, theillumination ring 158 may function as a mounting ring, as described,without having illumination functionality.

FIG. 5 depicts an exploded perspective view of the optical jog wheel 150of FIG. 3. As described above, the optical jog wheel 150 includes a backplate 154, a circuit substrate 152, a code wheel 104, a rotary dial 102,an independent button 156, and an illumination ring 158. In contrast tothe code wheel 102 of FIG. 2, the code wheel 102 shown in FIG. 5 isembodied in a ring implementation, rather than a disc implementation,although different shapes may be used.

In one embodiment, the optical jog wheel 150 also includes a mountingbracket 160. The mounting bracket 160 may function to secure the circuitsubstrate 152 to the back plate 154. The mounting bracket also mayprovide a predetermined mounting location for the code wheel 104. In oneembodiment, the illumination ring 158 includes an upper flange and oneor more lower fasteners such as plastic tabs to secure the severalcomponents between the illumination ring 158 and the base plate 154. Forexample, the lower fasteners may be inserted through holes in thecircuit substrate 152 and into fastener openings in the base plate 152,at which point the lower fasteners of the illumination ring 158 mayengage with the base plate 152.

FIG. 6 depicts one embodiment of a layout of an encoder 106 on a circuitsubstrate 152. The illustrated encoder 106 includes an emitter 120 and adetector 130. The detector 130 includes four photodiodes 132 arrangedrelative to the emitter 120, although fewer or more photodiodes 132 maybe used. In one embodiment, the photodiodes 132 are arranged so thatlight is incident on and reflected from the code wheel 104 approximatelyat a centerline 162 between the LED 122 of the emitter 120 and thephotodiodes 132 of the detector 130.

Various methods may be used to implement the emitter 120 and detector130. In one embodiment, the emitter 120 and detector 130 may beimplemented using chip-on-board technology. Alternatively, the emitter120 and detector 130 may be implemented as a discrete transfer moldedemitter-detector package. In one embodiment, the emitter 120 and decoder130 may be attached as bare dice onto the circuit substrate 152 toachieve a particular thickness of the optical jog wheel 150. In thisway, the emitter 120 and detector 130 may be die-attached close togetherto reduce or minimize the potential loss of light power. Additionally,the mounting of the emitter 120 and detector 130 may enable a small gapbetween the encoder 106 and the code wheel 104. The gap between theencoder 106 and the code wheel 104 also may depend on the use of anencapsulant, if any, to encapsulate part or all of the encoder 106.

FIG. 7 depicts a side view of one embodiment of a layout of an encoder106 with an air gap between the encoder 106 and the code wheel 104. Inparticular, the encoder 106 is not encapsulated by an encapsulant. Morespecifically, the emitter 120 and the decoder 130, including thephotodiodes 132, are not encapsulated, so the distance between theencoder 106 and the code wheel 104 may be reduced or minimized. Sincethe code wheel 104 is coupled to the rotary dial 102, and the encoder106 is coupled to the circuit substrate 152, the overall thickness ofthe optical jog wheel 150 may be reduced by reducing the distancebetween the encoder 106 and the code wheel 104.

FIG. 8 depicts a side view of one embodiment of a layout of an encoder106 with a fully encapsulated encoder 106. In particular, the emitter120 and detector 130, including the photodiodes 132, are encapsulated bya single encapsulant 164. In some embodiments, using a singleencapsulant may result in an increased distance between the encoder 106and the code wheel 104 because of the resulting height of theencapsulant 164. However, in some embodiments, the encapsulant may beformed using techniques to reduce the thickness of the encapsulant 164.

FIG. 9 depicts a side view of one embodiment of a layout of an encoder106 with an individually encapsulated emitter 120 and detector 130. Inparticular, the emitter 120 is encapsulated by a first encapsulant 164,and the detector 130 is encapsulated by a separate encapsulant 166 thatis distinct from the first encapsulant 164. In some embodiments, thefirst and second encapsulants 164 and 166 may be the same material,although different encapsulating materials may be used.

FIG. 10 depicts a side view of one embodiment of a layout of an encoder106 with an individually encapsulated emitter 120 and a partiallyencapsulated detector 130. In particular, the emitter 120 isencapsulated by a first encapsulant 164, and a portion of the detector130 is encapsulated by a second encapsulant 166. In one embodiment, thesecond encapsulant 166 encapsulates a wire bond 168 of the detector 130,but does not encapsulate the photodiodes 132. In other words, one ormore of the photodiodes 132 remains exposed.

FIG. 11 depicts one embodiment of a method 170 of making an optical jogwheel 150. While the method 170 depicts several operations, otherembodiments of the method 170 may include fewer or more operations formaking an optical jog wheel 150 or similar optical navigational device.

At block 172, a base plate 154 is provided. At block 174, a circuitsubstrate 152 is provided and coupled to the base plate 154. In oneembodiment, the circuit substrate 152 has an encoder 106, including anemitter 120 and detector 130, as described above. At block 176, amounting bracket 160 is coupled to the base plate 154. Various types ofconventional fasteners or coupling technologies may be used to couplethe mounting bracket 160 to the base plate 154. At block 178, a codewheel 104, a rotary dial 102, an independent button 156, and anillumination ring 158 are mounted to the mounting bracket 160.Alternatively, the code wheel 104, rotary dial 102, independent button156, and illumination ring 158 may be mounted to the base plate 154, asdescribed above.

FIG. 12 depicts one embodiment of a method 180 of using an optical jogwheel 150. However, it should be noted that this method 180 is exemplaryand other operations not discussed in conjunction with this method 180may be implemented by one or more embodiments of an optical jog wheel150 or similar optical navigational device.

At block 182, the emitter 120 emits a light signal incident on the track140 of the code wheel 104. At block 184, the incident light signalreflects off of the reflective sections 144 of the track 140, and thereflected light signal is detected by the detector 130. In oneembodiment, the reflected light signal is modulated according to theresolution and rotational speed of the code wheel 104. As explainedabove, the rotational speed of the code wheel 104 is the same as, orotherwise related to, the rotational speed of the rotary dial 102because the code wheel 104 is coupled to the rotary dial 102.

At block 186, the detector 130 generates one or more channel signalscorresponding to the modulated, reflected light signal. At block 188,the decoder 108 generates a count signal corresponding to the channelsignal(s) from the detector 130. At block 190, the microprocessor 110implements a user navigational operation in response to the count signalfrom the decoder 108. In this way, the microprocessor 110 implements auser navigational operation in response to a user navigational inputusing the rotary dial 102. The user navigational operation may be ascrolling operation, a selection operation, or another type ofnavigational operation on an electronic device.

FIG. 13 depicts a perspective view of another embodiment of an opticaljog wheel 150. The illustrated optical jog wheel 150 includes a rotarydial 102, a code wheel 104 (not shown in FIG. 3), a circuit substrate152, and a back plate 154. FIG. 14 depicts a side view of the opticaljog wheel 150 of FIG. 13.

FIG. 15 depicts an exploded perspective view of the optical jog wheel150 of FIG. 13. As described above, the optical jog wheel 150 includes aback plate 154, a circuit substrate 152, a mounting ring 160, a codewheel 104, a rotary dial 102, an independent button 156, and anillumination ring 158. In contrast to the optical jog wheel 150 of FIG.5, the optical jog wheel 150 of FIG. 15 reverses the order of theindependent button 156 and the illumination ring 158. In someembodiments, the order of the various components may be rearranged toaccommodate different mounting and securing combinations.

In one embodiment, the optical jog wheel 150 of FIG. 15 also includes ametal dome array 192. The metal dome array 150 includes one or moremetal dome switches to allow the rotary dial 102 to be used to makeselections. In one embodiment, a metal dome switch may be activated togenerate a switch signal when the rotary dial 102 is depressed atapproximately the location of a corresponding metal dome switch. Forexample, a user may activate a metal dome switch by tilting, ordepressing, a portion of the rotary dial 102 near the metal dome switch.The movement of the depressed portion of the rotary dial 102 toward themetal dome switch may engage and activate the metal dome switch. Variousarrangements for the metal dome array 192 may be implemented. Asdescribed above, the metal dome array 192 may be used in conjunctionwith the rotary dial 102 to allow a user to make a selection orimplement a user navigational operation.

FIG. 16 depicts a partial schematic diagram of another embodiment of acode wheel 200 with spiral track sections. In particular, FIG. 16illustrates a portion of a circular code wheel 200 in the shape of adisc. In some embodiments, the code wheel 200 may be in the shape of aring, rather than a disc. The illustrated code wheel 200 includes atrack 202, which may be a circular track that is concentric with thecode wheel 200. In one embodiment, the track 202 includes a continuousrepeating pattern that goes all the way around the code wheel 200. Thedepicted pattern includes alternating non-reflective sections 204 andreflective sections 206, although other patterns may be implemented. Inone embodiment, the non-reflective sections 204 are transparent sectionsof the code wheel 200 or, alternatively, are voids (e.g., holes) in thecode wheel 200. The reflective sections 206 are, for example, opaquesections in the code wheel 200. In one embodiment, the surface areascorresponding to the reflective sections 206 are coated with areflective material.

As described above, rotation of the code wheel 200 and, hence, the track202 results in modulation of the reflected light signal at the detector130 to measure positional changes of the code wheel 200 and the dial102. Other embodiments of the code wheel 200 may include other trackssuch as additional positional tracks or an index track, as are known inthe art.

In contrast to the code wheel 104 of FIG. 2, which is described above,the code wheel 200 of FIG. 16 includes a track 202 of alternatingspiral-shaped track sections 204 and 206 which form a circumferentialpath on the code wheel 200. In some embodiments, the reflective sections206 and the non-reflective sections 204 are approximately the same size.Other embodiments may use different sizes of reflective sections 206and/or non-reflective sections 204.

Each track section has a leading edge 208, a trailing edge 210, anoutside boundary 212 and an inside boundary 214. The edges 208 and 210and boundaries 212 and 214 may be curved or straight, depending on themethod of manufacture used to fabricate the code wheel 200. Someembodiments implement the boundaries 212 and 214 with circular arcsegments having a center coincidental with the center of the code wheel200. Additionally, in some embodiments, the trailing edge 210 issubstantially parallel to the leading edge 208. Other embodiments mayinclude non-parallel leading and trailing edges 208 and 210. It shouldbe noted that the leading edge of each of the track sections 208 and 210is substantially oblique to the direction of movement (indicated by thearrow) of the code wheel 200. Additionally, although an exemplarydirection of movement is shown, other embodiments may have a differentdirection of movement (e.g., the reverse direction), which may result indifferent designations for the leading and trailing edges of the tracksections 208 and 210.

FIG. 17 depicts a schematic layout 220 of one embodiment of aphotodetector array 222 relative to spiral track sections 204 a-c of thecode wheel 200 of FIG. 16. The spiral track sections 204 a-c mayrepresent either non-reflective track sections 204 or reflective tracksections 206. Although various shapes and sizes of photodetectors areadaptable for use in combination with the code wheel 200, someembodiments of the photodetector array 222 include interdigitatedphotodetectors formed on an integrated circuit substrate to maintain arelatively low production cost. In general, interdigitatedphotodetectors are substantially adjacent to one another and receiveinformation corresponding to more than one channel, as described above.The actual sizes, shapes, and layouts of the photodetectors may varydepending on the implementation of the code wheel 200 used with thephotodetector array 222. Signals from the photodetector array 222 may beprocessed as described above.

In one embodiment, the photodetector array 222 is located in a planethat is substantially parallel to the plane of the code wheel 200. Asthe code wheel 200 rotates, the circumferential track 202 of reflectiveand non-reflective sections 204 and 206 generates spiral-shaped lightimages (either through reflection or transmission) that are detected byone or more photodetectors of the photodetector array 222. In oneembodiment, the photodetector array 222 is oriented relative to thereflective sections 206 of the code wheel 200 so that the length of thephotodetectors are substantially parallel to the leading and trailingedges 208 and 210 of the reflective sections 206. Various geometricalequations may be used to determine the orientation of the photodetectorarray 222 relative to the reflective sections 206 of the code wheel 200.Some exemplary equations are described in U.S. Pat. No. 5,017,776, whichis incorporated by reference herein.

FIG. 18 depicts a schematic diagram of one embodiment of a code strip230 with a code track 232 which includes diagonal track sections 234 and236. Thus, in some embodiments, a linear coding element such as the codestrip 230 may be used instead of the circular code wheel 200. Similar tothe track sections 204 and 206 of the code wheel 200, the track section234 and 236 of the code strip 230 also have a leading edge 238, atrailing edge 240, an upper boundary 242, and a lower boundary 244.However, it should be noted that the designations of leading, trailing,upper, and lower are not restrictive of the physical layout of the tracksections 234 and 236. These designations merely indicate a direction ofmovement (indicated by the arrow) and/or a physical orientation of theencoder in which the code strip 230 might be implemented.

FIG. 19 depicts one embodiment of a method 250 of making an optical jogwheel 150 with the spiral code wheel 200 of FIG. 16. While the method250 depicts several operations, other embodiments of the method 250 mayinclude fewer or more operations for making an optical jog wheel 150with the spiral code wheel 200.

At block 252, the spiral code wheel 200 is coupled to a rotary dial 102.At block 254, an emitter 120 is mounted on a circuit substrate 152. Asdescribed above, the emitter 120 generates a light signal incident onthe track 202 of the spiral code wheel 200. At block 256, a detector 130is mounted on the circuit substrate 152. As described above, thedetector 130 detects a reflected spiral-shaped light signal reflectedoff of the track 202 of the spiral code wheel 200.

Other embodiments of the encoder also may include components fordetermining absolute position. For example, the encoder may includeadditional tracks, photodetectors, LEDs, or other components to allowthe encoder to determine an absolute angular position of the code wheelupon power up. The absolute angular position can be determined usingmany known techniques. One exemplary technique, with correspondinghardware, is described in more detail in U.S. patent application Ser.No. 11/445,661, filed on Jun. 2, 2006, entitled “Multi-bit absoluteposition optical encoder with reduced number of tracks,” which isincorporated by reference herein.

Although the operations of the method(s) herein are shown and describedin a particular order, the order of the operations of each method may bealtered so that certain operations may be performed in an inverse orderor so that certain operations may be performed, at least in part,concurrently with other operations. In another embodiment, instructionsor sub-operations of distinct operations may be implemented in anintermittent and/or alternating manner.

Although specific embodiments of the invention have been described andillustrated, the invention is not to be limited to the specific forms orarrangements of parts so described and illustrated. The scope of theinvention is to be defined by the claims appended hereto and theirequivalents.

1. A user navigational apparatus comprising: a dial; a coding elementcoupled to the dial, the coding element comprising a track ofalternating reflective and non-reflective sections located within aplane of the coding element, wherein each of the reflective andnon-reflective sections comprises a substantially oblique leading edgerelative to a direction of movement of the coding element; and anencoder comprising an emitter and a detector, the emitter configured togenerate a light signal incident on the track of the coding element, thedetector configured to detect a reflected light signal reflected off ofthe reflective sections of the track and to generate a channel signalcorresponding to the reflected light signal; a switch coupled to thedial, the switch to generate a first button click operation in responseto depression of only a portion of the dial; an independent buttondisposed within a center of the dial; a dome switch operationallycoupled to the independent button; and an illumination ringapproximately surrounding the independent button, wherein the dialcircumscribes the illumination ring and the independent button.
 2. Theuser navigational apparatus of claim 1 further comprising: a decodercoupled to the encoder, the decoder to generate a count signalcorresponding to the channel signal; and a microprocessor coupled to thedecoder, the microprocessor to implement a user navigational operationon a controlled device in response to a movement of the dial by a user.3. The user navigational apparatus of claim 2 wherein: the independentbutton is coupled to the microprocessor; wherein the microprocessor isfurther configured to implement a scrolling operation corresponding torotation of the dial, the first button click operation corresponding tothe depression of only the portion of the dial, or a second button clickoperation corresponding to a depression of the independent button; andwherein the scrolling operation manipulates display content on thecontrolled device.
 4. The user navigational apparatus of claim 3 whereinthe microprocessor is further configured to generate a signal toimplement a directional selection or an item selection on the controlleddevice in response to the depression of the dial or the depression ofthe independent button.
 5. The user navigational apparatus of claim 1further comprising: a back plate; a circuit substrate coupled to theback plate, wherein the encoder is coupled to the circuit substrate; anda mounting bracket coupled to the back plate, wherein the codingelement, the dial, the independent button, and the illumination ring aremounted to the mounting bracket.
 6. The user navigational apparatus ofclaim 1 wherein the detector comprises: a photodiode to detect thereflected light signal reflected off of the reflective sections of thetrack; and signal processing circuitry coupled to the photodiode, thesignal processing circuitry to generate the channel signal correspondingto the reflected light signal.
 7. The user navigational apparatus ofclaim 6 further comprising an air gap between the coding element and theemitter and between the coding element and the detector, wherein theemitter and the detector are not encapsulated by an encapsulant.
 8. Theuser navigational apparatus of claim 6 further comprising an encapsulantto jointly encapsulate the emitter and the detector.
 9. The usernavigational apparatus of claim 6 further comprising: a firstencapsulant to encapsulate the emitter; and a second encapsulant toencapsulate the detector.
 10. The user navigational apparatus of claim 6further comprising: a first encapsulant to encapsulate the emitter; anda second encapsulant to encapsulate a wire bond of the detector, whereinthe second encapsulant does not encapsulate the photodiode.
 11. The usernavigational apparatus of claim 1 wherein the encoder comprises anincremental, multi-turn, multi-channel, rotary encoder.
 12. The usernavigational apparatus of claim 1 wherein the encoder comprises achip-on-board emitter and detector or a discrete transfer moldedemitter-detector package.
 13. The user navigational apparatus of claim 1wherein the code wheel is a flat ring.